Ewing's sarcoma. Pathology, tissue culture, and cytogenetics

Primary Ewing's sarcoma of the talus

Ewing's sarcoma is a malignant round cell tumour of bones and soft tissues that usually arises from the diaphyseal or meta-diaphyseal parts of long bones and less commonly from flat bones. It occurs rarely in the foot and if occurs, the calcaneus and the metatarsals are commonly involved. We present a case of a young woman diagnosed with primary Ewing's sarcoma of the talus with local spread to adjacent tarsals and the ankle joint. Ewing's sarcoma of feet, if present with even a trivial suspicion of spread either locally or distant, makes limb salvage surgery difficult. So, the treatment with radical surgery or by combined chemotherapy and radiotherapy should be considered-keeping in mind the complex anatomy of the foot and the difficulty in achieving tumour-free margins. Based on this experience, she underwent below-knee amputation. The patient received adjuvant chemotherapy and survived with a disease-free survival at the latest follow-up of 1 year.

Total Talectomy and Reconstruction Using a 3-dimensional Printed Talus Prosthesis for Ewing's Sarcoma: A 3.5-Year Follow-up

Ewing's sarcoma is extremely rare in the foot. Below the knee amputation is indicated for most primary malignant bone tumors of the hindfoot, with few cases of successful limb salvage surgery having been reported. The use of 3-dimensional printed implants may successfully address reconstruction challenges after tumor resection. The authors present a case of a 30-year-old woman with a Ewing's sarcoma of the talus who underwent total talectomy and replacement of the entire talus with a custom-made 3-dimensional printed talar prosthesis. [Orthopedics. 2019; 42(4):e405-e409.].

Cytogenetic characterization of Ewing tumors using fine needle aspiration samples. a 10-year experience and review of the literature

Chromosomal analysis was performed in fine needle aspiration samples of 98 primary Ewing tumors (ETs) prior to treatment. Among the 58 (59.18%) successful cultures, t(11;22)(q24;q12) was observed in 87.9% and 6.8% had abnormalities other than t(11;22), viz., del(22)(q12), der(16)t(1;16)(q12;q11), and variant t(8;22)(q24;q12). Involvement of breakpoints 1q21, 1q22, 3p14, 16q22, and 17p13 was also observed. Numerical abnormalities such as trisomies 8 and 12 were found in 29.3% and 20.6% and trisomy 18 in 17.2%. An attempt was made to evaluate the role of these additional changes in the process of tumor development, metastasis, and progression of the disease. This is the largest cytogenetic study on ET from a single center using a simple and reliable technique of fine-needle aspiration culture. The literature on cytogenetics of ET is reviewed.

DNA ploidy of liver biopsies from patients with liver cirrhosis and hepatocellular carcinoma: a flow cytometric analysis

Flow cytometric DNA analysis was used to assess cellular kinetics of needle liver biopsies from patients with liver cirrhosis and hepatocellular carcinoma (HCC). An abnormal DNA content was shown in 44.5% of liver cirrhosis cases and in 78.6% of tumor sites. The number of proliferating cells (S + G2M%) was significantly increased in cirrhotic liver (P < 0.05). Dysplasia was found in 66% of cirrhotic specimens. All negative dysplasia specimens showed a diploid pattern while 69% of positive dysplastic specimens were aneuploid (P < 0.001). In conclusion, cell proliferation, aneuploidy and liver cell dysplasia are important indicators in liver cirrhosis for the development of HCC.

Case of extra pulmonary, pleuro-pulmonary blastoma in a child: pathological and cytogenetic findings

We report the cytogenetic findings in a case of Pleuro-Pulmonary Blastoma of Childhood Type II. This is a rare intrathoracic tumour that can occur in the lungs with up to 25% of cases being extra pulmonary.

The World Health Organization's histologic classification of bone tumors. A commentary on the second edition

BACKGROUND

The World Health Organization's histologic classification of bone tumors was revised in 1993.

METHODS

The first edition was reviewed by an international panel of pathologists from nine countries and modified to incorporate advances made in the twenty years since it appeared.

RESULTS

The framework and concept of the classification remain the same (i.e., based on histologic criteria in terms of differentiation shown by the tumor cells via conventional light microscopy supplemented by immunohistochemistry). New entities not described in the first edition include, for example, benign and malignant fibrous histiocytomas, well differentiated osteosarcoma, round-cell osteosarcoma, clear cell chondrosarcoma, primitive neuroectodermal tumor of bone, osteofibrous dysplasia, and giant cell reparative granuloma.

CONCLUSION

The revised and expanded classification reflects advances in our knowledge, but is similar in concept and framework to the original version to allow comparisons between data collected in the past and future.

FNA biopsy of small round cell tumors of childhood: cytomorphologic features and the role of ancillary studies

Pediatric tumors which are conventionally considered to be small round cell tumors (SRCTs) include the prototypical neuroblastoma as well as rhabdomyosarcoma (RMS), Ewing's sarcoma (ES), malignant lymphoma, and primitive neuroectodermal tumor (PNET). Other malignancies may be considered in the differential diagnosis such as small-cell osteogenic sarcoma, undifferentiated (anaplastic) hepatoblastoma, granulocytic sarcoma, blastemal type Wilms' tumor, and desmoplastic small-cell tumor of the peritoneum. The cytomorphologic features of conventional SRCTs is presented as well as the utility of ancillary studies performed on the aspirated material in making a specific and correct diagnosis. The role of the immediate cytologic assessment of the aspirate is stress, since this is a critical step in formulating an initial diagnostic impression that should prompt the need for additional material for pertinent ancillary studies. Although challenging, FNA cytology of SRCTs of childhood can be diagnostic in the majority of cases, allowing specific therapy to be given to patients with unresectable SRCTs without a tissue biopsy as well as documenting recurrent and/or metastatic disease.

Bone tumors other than osteosarcoma after retinoblastoma

BACKGROUND

The most frequent second malignant neoplasm after retinoblastoma is osteosarcoma, which may be associated with radiation therapy or arise de novo in patients with bilateral retinoblastoma.

METHODS

Clinical, pathologic, and diagnostic imaging findings in two patients with Ewing sarcoma (ES) and one with peripheral neuroepithelioma (PN) are presented.

RESULTS

Second malignant neoplasms located in the extremities or pelvis were seen 12-18 years after initial diagnosis of unilateral (two patients) or bilateral (one patient) retinoblastoma. The patients with unilateral retinoblastoma were treated by enucleation only; the other received ocular radiation therapy and chemotherapy. To the knowledge of the authors, this is the first documentation of round blue cell tumor after unilateral retinoblastoma.

CONCLUSIONS

ES and PN should be included in the differential diagnosis of malignant neoplasms occurring after treatment of unilateral or bilateral retinoblastoma.

Cytogenetic and pathologic aspects of Ewing's sarcoma and neuroectodermal tumors

Diagnostic classification of poorly differentiated, round cell, primitive neuroectodermal neoplasms, including Ewing's sarcoma, peripheral neuroepithelioma, Askin's tumor, and esthesioneuroblastoma, is challenging to the surgical pathologist using conventional histopathologic approaches because of very similar and overlapping morphologic and cytologic features. Furthermore, distinguishing these neoplasms from neuroblastoma, embryonal rhabdomyosarcoma, small cell osteogenic sarcoma, and non-Hodgkin's lymphoma can be difficult. This paper describes and reviews the cytogenetic and molecular genetic changes in these tumors and demonstrates how the ability to detect these changes has enabled a greater understanding of the histogenesis, classification, diagnosis, and prognosis of these neoplasms.

Establishment and characterization of a new Ewing's sarcoma cell line

A new human Ewing's sarcoma cell line (CADO-ES1) was established from the malignant pleural effusion of a 19-year-old woman. These cells grew both anchorage dependently and anchorage independently. When cultured in bacteriologic dishes, they grew as tightly packed multicellular tumor spheroids; they were also capable of proliferating in soft agar. Flow cytometric DNA analysis demonstrated a nearly diploid DNA content (DNA index = 0.902). Chromosomal studies of cultured cells showed an isodicentric chromosome 8 in all examined cells, but t(11;22)(q24;q12), a translocation reported previously in Ewing's sarcoma, was not detected. Under normal culture conditions, no morphologic evidence of neural differentiation was detected. In addition, immunocytochemical studies showed that vimentin was intensely positive, whereas neurofilament (NF) and neuron-specific enolase (NSE) were weakly positive. Treatment with cyclic AMP (cAMP) induced pronounced morphologic evidence of neural differentiation and strong expression of NF in cultured cells. S-100 protein, glial fibrillary acidic protein (GFAP), desmin, cytokeratin, and epithelial membrane antigen were not detected immunohistochemically in either untreated or cAMP-treated cells, however. These data suggest that this cell line is derived from a highly undifferentiated neural cell with high chromosomal clonality, differentiating into neural features under certain conditions.

Flow cytometric DNA analysis of hepatocellular carcinoma

The prognostic value of nuclear DNA content was studied retrospectively using flow cytometry in 203 cases of resected hepatocellular carcinoma. The occurrence of DNA aneuploidy, which was detected in 50% of patients, correlated significantly with tumor size and the presence of vascular invasion or intrahepatic metastasis. Overall, patients with DNA aneuploid tumors had a significantly worse prognosis than those with DNA diploid tumors (P less than 0.001) and, also in subdivided groups by tumor size (P less than 0.01). Among DNA aneuploid patients, the survival times were significantly shorter for patients with a low DNA index (less than 1.5) than for those with a high DNA index (greater than or equal to 1.5) (P less than 0.05). In a Cox multivariate analysis, nuclear DNA content provided significant prognostic value (P = 0.008), as did vascular invasion (P = 0.001) and intrahepatic metastasis (P = 0.005). These results indicated that nuclear DNA content has an important prognostic value in hepatocellular carcinoma.

t(11;22) in three cases of peripheral neuroepithelioma

Short-term cultures of three cases of peripheral neuroepitheliomas were studied using G-banding technique. A t(11;22)(q24;q12) was recognized in all three tumors. The results strengthen the hypothesis of a common histogenesis for neuroepithelioma, Ewing's sarcoma, and the Askin tumor.

Isolated CNS involvement in Ewing's sarcoma

Ewing's sarcoma, an uncommon malignant neoplasm of bone, represents about 10% of all the malignant primary bone tumors. The assumption that subclinical metastases are already present in patients with apparently localized tumor indicates the need for systemic therapy as an integral part of primary treatment. The usual sites of metastases are the lungs and skeletal system. Central nervous system (CNS) involvement is rare and is usually seen only in disseminated and fairly advanced disease. We report two patients in whom, after aggressive adjuvant chemotherapy, disease developed in the CNS without local recurrence. In one patient, meningeal involvement with malignant cells was identifiable in the cerebrospinal fluid; in the second patient, who presented with a space-occupying lesion, a diagnosis of arachnoid involvement was made histologically.

Comparative study of neuroectodermal tumor and Ewing's sarcoma of the bone. Histopathologic, immunohistochemical and ultrastructural features

We carried out a histologic, immunohistochemical and ultrastructural study of 19 tumors, previously classified as Ewing's sarcoma of the bone (ESB). The tumors were categorized histologically into four groups according to the presence or absence and the distribution of Homer-Wright rosettes, together with the immunohistochemical and ultrastructural features: 1) neuroectodermal tumor of bone (NTB) with diffusely dispersed rosettes (4 cases), 2) conventional ESB totally lacking the rosettes (9 cases), 3) intermediate-type tumor with characteristics of both NTB and ESB (4 cases), and 4) spindle cell-type tumor with focal rosettes (2 cases). Ultrastructurally, NTB contained neurotubules and neurosecretory granules, whereas ESB consisted of only undifferentiated cells. Immunoreactivity with antineural antibodies, such as Leu-7, and those against synaptophysin, NSE, neurofilament, and chromogranin, was detected in the majority of NTB, in intermediate- and spindle cell-type tumors and in two of the nine cases of ESB. In view of these findings, we propose that use of the term "neuroectodermal tumor of the bone" should be restricted to tumors with an extensive distribution of rosettes, and that those without unequivocal rosettes should be classified as ESB, although ESB may be the most undifferentiated form of NTB and some overlap may occur between the two tumor types.

Ewing's sarcoma. A retrospective study of histological and immunohistochemical factors and their relation to prognosis

Histological and immunohistochemical features of 87 patients with conventionally diagnosed Ewing's sarcoma were studied retrospectively on routinely processed material and evaluated with regard to prognostic significance. 74% were convincingly positive when stained for vimentin, 13% were doubtful, and 13% were negative. A varying degree of positivity for neuron-specific enolase (NSE) was found in 15%; these cases all co-expressed vimentin. A single tumour contained scattered cytokeratin-positive cells. Positivity for the leukocyte common antigen (LCA) could be demonstrated in three cases; these were excluded from the statistical analysis of prognostic factors. Growth pattern, soft tissue invasion, monomorphic or dimorphic cell population, and PAS-, NSE- or vimentin-positivity did not influence survival significantly. However, prognosis was increasingly poor with increasing degree of necrosis: median survival was 28 months for grade I necrosis (less than 10%), 16 months for grade II (10-50%), and 11 months for grade III (greater than 50%), p less than 0.0005. A mitosis count of less than 1 per high-powerfield (HPF) was correlated to a median survival of 26 months, greater than or equal to 1 per HPF to 12 months, p less than 0.05. The findings indicate some degree of heterogeneity in Ewing's sarcoma which may be related to primitive peripheral neuroectodermal tumours (PNETs), or be a true blastoma. In future trials, diagnostic criteria (including immunohistochemistry) should be clearly defined and materials should be large enough to allow for stratification according to prognostic factors.

Two new cases of primary peripheral neuroepithelioma of soft tissue with translocation t(11;22)(q24;q12)

A direct cytogenetic analysis was performed on tumor samples obtained from two patients with clinical and histopathologic diagnosis of primary peripheral neuroepithelioma. Both tumors presented the translocation t(11;22)(q24;q12). These results confirm those previously obtained by other authors and suggest a common histogenetic origin for this tumor with Ewing's sarcoma and Askin's tumor, in which the same translocation has been described.

Chromosomes in Ewing's sarcoma. I. An evaluation of 85 cases of remarkable consistency of t(11;22)(q24;q12)

Since our initial reports on chromosomal studies in eight Ewing's sarcomas (ES), we have carried out similar investigations on 23 additional ES specimens following short-term culture of tumor cells (16 cases), and established in vitro cell lines (three cases) and on xenografted tumors in nude mice (four cases). We demonstrated the presence of the reciprocal t(11;22)(q24;q12) in every case except one that exhibited a complex t(11;22;14)(q24;q12;q11). On the basis of results from these additional 23 cases, we confirm the consistency of the t(11;22)(q24;q12) in ES. Moreover, we reviewed 54 ES cases reported by other investigators; when added to our 31 cases, this brings the total number to 85 unrelated cases of ES available for an evaluation of the frequency of involvement of bands 11q24 and 22q12 in translocations in ES. The standard t(11;22)(q24;q12) proved to be a remarkably consistent event, present in 83% of the cases. Five percent of the cases exhibited complex translocations involving a third chromosome in addition to chromosomes #11 and #22. In 4% of the cases variant translocations involved 22q12 but with a chromosome(s) other than #11. The breakpoint on chromosome 22q12 appears to be the most consistently observed event in 92% of the cases, whereas, the breakpoint at chromosome 11q24 was observed in 88% of the cases.

Chromosomes in Ewing's sarcoma. II. Nonrandom additional changes, trisomy 8 and der(16)t(1;16)

Chromosomal data from 82 informative, unrelated Ewing's sarcoma (ES) specimens (including 20 personal specimens) were reviewed for secondary changes additional to the t(11;22)(q24;q12). Additional numerical and/or structural changes were found in 75 specimens. Trisomy 8 was observed consistently in half of the 43 cases selected for analysis of numerical changes. A nonrandom der(16) was observed as a result of an unbalanced t(1;16) in 18% of the 82 analyzed for structural changes. Consistent involvement of chromosome #16 in rearrangements with chromosome #1 may be an additional chromosome change specifically associated with ES.